Typical existing electric powered steam generating systems and boilers heat water using electric resistance elements arranged inside a holding reservoir (e.g., a tank or pressure vessel). The reservoir contains water which usually is heated via submerged electric tubular heaters located in the reservoir. These heaters usually operate in a static environment by raising a controlled quantity of water to a prescribed temperature, then releasing that water as required in the form of saturated steam. When steam is required in a typical existing steam generator, water moves from the holding reservoir through a throttle valve, converting the liquid into a saturated steam.
The reservoir typically has a high and low level switch to control water height in the reservoir which introduces ambient temperature water to the reservoir as necessary. When mixed with the water already in the reservoir, this water can lower the temperature of the reservoir water to a temperature lower than that needed to produce operational steam, thus requiring recuperative heating time before steam can be once again generated.
Existing electric powered steam generating systems and boilers can be operationally inefficient. For example, existing electric powered steam generating systems can possess a large thermal mass that must be overcome at start-up. As a result, the amount of time required to reach operating temperature at start-up can be prolonged. In some instances, existing electric powered steam generating systems can require 10 to 15 minutes or more of start-up time from a cold start before they can produce high quality steam.
Existing electric powered steam generating systems can also require continuous supplies of energy to offset thermal losses through the piping network supplying the system and through the insulating layers that can surround holding reservoirs. For example, existing electric powered steam generating systems can require continuous sporadic activation of heating elements, e.g., reservoir heating elements, to maintain water temperature in attempts to avoid re-initiating the start-up process.